On the morning of February 1, 2003, the Space Shuttle Columbia underwent a high-altitude, high-velocity breakup during the entry-to-landing phase of flight. The external investigation by the Columbia Accident Investigation Board (CAIB) provided the overall causes of the accident in a report that included an analysis by the Crew Survivability Working Group to determine the cause of the crewmembers' deaths and the lessons learned. The next year the Space Shuttle Program commissioned the Spacecraft Crew Survival Integrated Investigation Team to perform a comprehensive analysis of the accident, focusing on factors and events affecting crew safety and developing recommendations for improving crew survival for future human space flight. This report was published in December 2008.

Loss of Signal presents the aeromedical lessons learned from the Columbia accident that will enhance crew safety and survival on human space flight missions. These lessons were presented to limited audiences at three separate Aerospace Medical Association (AsMA) conferences: in 2004 in Anchorage, Alaska, on the causes of the accident; in 2005 in Kansas City, Missouri, on the response, recovery, and identification aspects of the investigation; and in 2011, again in Anchorage, Alaska, on future implications for human space flight. As we are embarking on the development of new spacefaring vehicles through both government and commercial efforts, the NASA Johnson Space Center Space Life Sciences Directorate (SLSD)1 proceeded to make this information available to a wider audience engaged in the design and development of future space vehicles.

Historically, the SLSD has always prepared for space flight mishaps. From the beginning of the Space Shuttle Program with the launch of the first Space Shuttle mission in 1981 through the Challenger accident in 1986, the SLSD interfaced with the Department of Defense Manned Space Flight Program Support Office (DOD DDMS), Patrick Air Force Base, Florida, with preparation for launch and landing emergencies. After the Challenger accident, these efforts were upgraded by enhancing crew safety including improved egress, escape, and bail-out procedures with the new Launch Entry Suit. In preparation for return to flight in 1988, the SLSD developed a flight surgeon training program, the Space Operations Medical Support Training Course. These improvements led to a more direct interface of NASA with DOD DDMS in training medical personnel and trauma teams at landing sites in the United States and international locations on equipment, procedures, and communications for response, search, rescue, and recovery operations. In 1998, the SLSD Medical Operations Branch formed a Contingency Medical Group, a cadre of flight surgeons that specialized in preparation for any aviation and spacecraft mishap. This group met with the Office of Armed Forces Medical Examiner and Armed Forces Institute of Pathology2 in 1999 to renew and improve the SLSD relationships with these organizations for mishap investigations. This coordination greatly assisted the recovery and identification efforts during the Columbia tragedy.

Loss of Signal summarizes and consolidates the aeromedical impacts of the Columbia mishap process-- the response, recovery, identification, investigative studies, medical and legal forensic analysis, and future preparation that are needed to respond to spacecraft mishaps. The goal of this book is to provide an account of the aeromedical aspects of the Columbia accident and the investigation that followed, and to encourage aerospace medical specialists to continue to capture information, learn from it, and improve procedures and spacecraft designs for the safety of future crews.